Device for sealing food containers and the like



Jan. 6, 1970 J. H. L. M. PIZARRO l 3,488,472

DEVICE FOR SEALING FOOD CONTA INERS `AND THE LIKE Filed May 5. 1967 5a 5b 12b 12a. 1

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l y l. 7 R09 u \\1 @WJ ATre/vey United States Patent O Inf. cl. Hosb 1/00, 3/02 U.S. Cl. 219-243 7 Claims ABSTRACT OF THE DISCLOSURE Quick-acting device for the sealing of food containers or the like, having a base formed with a frustoconical recess surrounded by a shoulder with an annular groove to receive the brim of a container, this base having hinged to it a heated cover with an annular rib bearing upon the shoulder and fitting into the annular groove thereof to fuse an adhesive-coated lid onto the container brim upon closure of the cover. One or more frustoconical shells with similarly grooved upper peripheral edges may be nested in the recess to accommodate containers of different sizes, their grooved edges being preferably staggered vertically With reference to one another and to the shoulder of the base; the cover is then provided with correspondingly staggered additional annular ribs forming with the first-mentioned rib a concentric array.

My present invention relates to a device for the sealing of food containers or the like by means of a at, diskshaped lid having a heat-softenable (e.g. thermoplastic) adhesive applied to its underside.

The sealing of such containers by the simultaneous application of heat and pressure must be carried out in the shortest possible time, not only to speed up production but also to prevent spoilage of the contents (especially food) by prolonged exposure to high temperatures.

It is, therefore, the general object of my invention to provide a device of simple construction adapted for the rapid heat-sealing of such containers.

A more particular object of the invention is to provide a device of this character capable of accommodating containers of diiierent sizes.

In accordance with this invention I provide a device which comprises a base and a removable cover, preferably hinged to the base, having co-operating formations for clamping the brim of a container and an overlying peripheral lid portion between them, in combination with heating means such as an electric resistance plate disposed within the cover. The base is formed with an upwardly open recess of frustoconical shape for the quick insertion and removal of a correspondingly shaped container whose brim overlies an annular shoulder of the base surrounding the recess; the cover has an annular formation which registers with that shoulder in a position of closure to exert pressure upon the container brim and an adhesively coated lid placed on top of it, this formation being advantageously a rib fitting into an annular groove of the brim-supporting shoulder to deform the brim and the lid periphery during the clamping process. To accommodate containers of different sizes, I may provide one or more frustoconical shells which can be received in nested relationship within the recess of the base and which are provided along their upper peripheral edges with similar annular shoulders co-operating with corresponding ribs on the cover. To insure the development of uniform clamping pressure regardless of the presence or absence of these shells, I prefer to disposed the grooved shoulders or edges of the base and the shells at progressively higher 3,488,472 Patented Jan. 6, 1970 levels with corresponding vertical staggering of theconcentric annular ribs on the cover. It is also desirable to locate the hinge axis of the cover substantially at the level of the highest edge in order to have the cover move substantially axially off the brim of the smallest container; this measure allows for small spacing of the innermost clamping rib from the next-outer rib without any interference of the latter rib with the projecting top of the innermost shell.

The invention will be described in greater detail with reference to the accompanying drawing in which:

FIG. 1 is a perspective view of my sealing device in its closed state;

FIG. 2 is a cross-sectional view taken on the line II-II of FIG. 1;

FIG. 3 is a view similar to FIG. 2 in a partly open postion; and

FIG. 4 is an exploded elevational view, partly in section, of the device in its open state together with a container and lid to be bonded together.

The device shown in the drawing comprises a base 1 and a cover 2 hinged thereto at 3. Base 1 is formed with a frustoconical recess 4 surrounded by a raised annular shoulder 11 provided with an annular groove 12. An annular rib 7 on the underside of the cover 2 iits into groove 12, with just enough clearance to leave room for two layers of metal (eg. aluminum) foil or other container material to be heat-sealed to each other. In order to accommodate containers of different sizes, several frustoconical shells Sa, 5b can be nestedly disposed in recess 4 of base 1; each of these inserts has an upper peripheral edge with an annular groove 12m, 12b respectively cooperating with an annular rib 7a, 7b 0n cover 2. The annular surfaces carrying grooves 12, 12a, 12b are located at progressively higher levels when the inserts 5a, 5b are in place, the concentric ribs 7, 7a, 7b being similarly staggered in elevation. Hinge 3 lies approximately on the level of groove 12b to minimize interference between the top of shell 5b and the surrounding annular rib 7a during the opening and closing of the cover. The projecting upper marginal zones of the outer frustoconical surfaces of shells 5a and 5b are cut olf cylindrically for the same purpose.

A handle 6 serves for manually swinging the cover 2 about the axis of its hinge 3 and bringing the ribs 7, 7a, 7b down under pressure upon the confronting grooved surfaces. It, as shown in FIG. 4, the innermost shell 5b is in place and has its top overlain by the brim 13 of a container 14, this brim in turn being covered by a diskshaped lid 15 of substantially the same dia-meter coated on its underside with a thermally fusible adhesive (e.g. a polyester), the lid and the brim are clamped between the rib 7b and the grooved upper surface of shell 5b and are deformed to the shape of groove 12b for a more positive sealing effect. A resistance element 8 in a heating disk 9, disposed in a chamber 16 of cover 2, is energized via a flexible cable 17 terminating in a plug 1-8; the temperature developed by this heater is controlled by the thermostat 10 in chamber 16. Cover 2 is made in two parts held together by a screw 19.

Shoulder 11 and the tops of inserts 5a, 5b are so stepped that all the grooves 12, 12a, 12b are concurrently engaged by their respective ribs 7, 7a, 7b when no container brim and lid are interposed therebetween; thus, the presence of such elements (as in FIG. 2) causes a slight spacing to remain between the monutilized grooves and ribs. This insures that the full pressure applied to handle 6 will be brought to bear upon the elements clamped between the cover 2 and the base 1 regardless of the presence or absence of inserts 5a, 5b.

The container 14 may be of the type made from a flat metal foil so as to exhibit a corrugated frustoconical periphery and a wrinkled brim. In that case, the brim proper may be covered by an intermediate smooth-surfaced ring adhesively bonded thereto, the adhesive (e.g. polyester) filling the wrinkles of the metal foil, before the lid 15 is applied; this improvement has been described and claimed in my copending application Ser. No. 636,- 321 of even date.

I claim:

1. A device for the sealing of containers, comprising a base provided with an upwardly open frustoconical recess surrounded by a planar shoulder defining the mouth of said recess, a cover removably overlying said base and provided with an annular formation registering with said shoulder in a closed position of said cover, heating means in said cover for thermally bonding an adhesive-coated lid onto a brim of a container lodged in said recess upon a clamping of said brim and said lid between said shoulder and said formation, at least one upwardly open frus toconical shell nestedly received in 4said recess for accommodating a similar container to be of smaller size, said shell having a peripheral planar edge disposed in a plane above the plane of said shoulder, said cover having a second annular formation concentrically disposed in the first annular formation to register with the peripheral edge of said shell, said shoulder and said edge being formed with respective coaxial annular grooves, said formations being ribs lying in planes one below the other and matingly receivable in said grooves of said shoulder and said edge respectively for deforming a lid the respective brim of a container.

2. A device as defined in claim 1 wherein said cover is hinged to said base.

3. A device as defined in claim 1, further comprising a plurality of frustoconical shells of progressively decreasing diameter nestedly received in said recess for accommodating respective containers of smaller sizes, said cover having a plurality of additional annular formations respectively registering with the peripheral edges of said shells and forming a concentric array with the first annular formation.

4. A device as defined in claim 3 wherein said shoulder and said peripheral edges are disposed at progressively higher levels, said annular formations being correspondingly staggered in vertical direction.

5. A device as defined in clai-m 4 wherein said cover is hinged to said base substantially at the level of the highest peripheral edge.

6. A device as defined in claim 3 wherein said shoulder and each of said peripheral e'dges are formed with respective annular grooves, said annular formations being ribs matingly receivable in said grooves for deforming the lids and brims of the respective containers therebetween.

7. A device as defined in claim 3 wherein said heating means comprises a disk in said cover overlying the re'- gion of said concentric array.

References Cited UNITED STATES PATENTS 291,681 1/1884 Chamberlain et al. 72-61 893,469 7/ 1908 Essmuller. 2,896,555 7/ 1959 Marcus et al 107-l.5 X 3,102,182 8/1963 OelZe et al. 156-583 X 3,309,836 3/ 1967 Hallowell 53--373 X JOSEPH V. TRUHE, Primary Examiner PETER W. GOWDEY, Assistant Examiner U.S. C1. X.R. 53--329, 373 

